Crime drove away Detroit's taxpayers. Much residential and commercial property is literally worthless. The Detroit News found that 47 percent of property owners didn't pay property taxes in 2011.
The city workforce is not huge (9,700), and its pensions are not lavish (average: $19,000). But the city lacks a tax base sufficient to pay for services for 713,777 people over 139 square miles.
Stockton and San Bernardino are different. They are typical of mid-sized California cities that were never upscale and have been filling up with immigrants -- many of them illegal, primarily from Mexico. Stockton is 40 percent Hispanic; San Bernardino 60 percent.
Public employee unions, legalized by Jerry Brown in his first stint as governor nearly 40 years ago, are strong in California, and in these two cities, as in Vallejo, which went bankrupt in 2008, succeeded in getting lavish salaries, health plans and pensions before the housing bust.
Police and fire unions were especially demanding. You have to meet the competition of richer neighboring cities or lose your public safety officials, they threatened.
After all, housing prices were always going to rise, and federal policies and Fannie Mae encouraged huge mortgages for Hispanics. So the property tax base would always keep rising. What could go wrong?
The 2007-10 foreclosure rates in the Central Valley (Stockton) and the Inland Empire (San Bernardino) were among the nation's highest. I suspect that half the dispossessed homeowners were Hispanic.
These two cities had other problems. Stockton spent $1 billion on downtown and waterfront infrastructure that has been a bust. San Bernardino officials reportedly falsified documents on pension costs.
Economic downturns expose weaknesses and mistakes that are ignored in more prosperous times.
Detroit is in bankruptcy primarily because crime drove out the city's tax base. The California cities are there primarily because of overbearing public employee unions.
They're probably not the last cities to go bankrupt for these reasons.